It is common in hydrocarbon well operations to have two or more fluids flowing through a downhole tubular positioned in a wellbore extending through a subterranean zone. For example, during production, the fluids in the wellbore tend to separate into zones of gas, water, and oil flow. Such flow phase separation can create unwanted flow instabilities and oscillations. Also, if the gas separates from the oil, the oil is no longer lightened by the gas and can collect in the bottom of the well which would reduce oil production. During injection of steam, mist flow conditions can arise where liquid water sheets down the wall of the injection tubing while the gaseous steam flows down the middle of the tubing. During multi-zonal injection, such as with Halliburton Energy Services, Inc.'s commercially available ZoneMaster (trade name) tool, separation of gaseous and liquid water often results in unequal gaseous and liquid injection distribution across the wellbore; that is, a relatively greater amount of steam is injected into the upper zones and a relatively greater amount of water is injected into the lower zones. During hydrajet fracturing, a distribution of cutting particles is created in the cross-section of flow. The result is more particles in the center of the tubing and fewer particles towards the tubing wall. This particle distribution tends to result in fewer particles being injected into the upper zones and more particles being injected into the lower zones. Similarly, it is believed this effect may be significant in hydraulic fracturing with regard to proppant distribution in the tubing and proppant concentration depending on exit port locations along the work string.
Downhole mixers are used to mix and homogenize the fluid flow. Dynamic and powered mixer devices may require power sources, effectively block tool passage through the tubing string in the wellbore, or create significant pressure drops across the mixer device. Similarly, downhole static mixer devices often block tool passage, create unwanted pressure drops, or fail to provide desired homogenization. Therefore, a need exists for a downhole static mixer for mixing and homogenizing constituent parts of the downhole fluid flow without blocking tool passage through the tubing string.